vzdump.adoc

   1 ifdef::manvolnum[]
   2 PVE({manvolnum})
   3 ================
   4 include::attributes.txt[]
   5
   6 NAME
   7 ----
   8
   9 vzdump - Backup Utility for VMs and Containers
  10
  11
  12 SYNOPSYS
  13 --------
  14
  15 include::vzdump.1-synopsis.adoc[]
  16
  17
  18 DESCRIPTION
  19 -----------
  20 endif::manvolnum[]
  21
  22 ifndef::manvolnum[]
  23 Backup and Restore
  24 ==================
  25 include::attributes.txt[]
  26 endif::manvolnum[]
  27
  28 'vzdump' is a utility to make consistent backups of running guest
  29 systems. It basically creates an archive of the guest private area,
  30 which also includes the guest configuration files. 'vzdump' currently
  31 supports LXC containers and QemuServer VMs. There are several ways to
  32 provide consistency (option `mode`), depending on the guest type.
  33
  34 .Backup `mode` for VMs:
  35
  36 `stop` mode::
  37
  38 This first performns a clean shutdown of the VM to make sure it is
  39 stopped. It then starts the VM in suspended mode and uses the qemu
  40 backup feature to dump all data. If the VM was running, we start
  41 (resume) it immediately after starting the qemu backup task. This
  42 keeps the downtime as low as possible.
  43
  44 `suspend` mode::
  45
  46 This mode does not really make sense for qemu. Please use snapshot
  47 mode instead.
  48
  49 `snapshot` mode::
  50
  51 This mode simply starts a qemu live backup task. If the guest agent
  52 is enabled (`agent: 1`) and running, it calls 'guest-fsfreeze-freeze'
  53 and 'guest-fsfreeze-thaw' to improve consistency.
  54
  55 A technical overview of the Proxmox VE live backup for QemuServer can
  56 be found online
  57 https://git.proxmox.com/?p=pve-qemu-kvm.git;a=blob;f=backup.txt[here].
  58
  59 NOTE: Qemu backup provides snapshots on any storage type. It does
  60 not require that the underlying storage supports snapshots.
  61
  62
  63 .Backup `mode` for Containers:
  64
  65 `stop` mode::
  66
  67 Stop the container for the duration of the backup. This potentially results in
  68 a very long downtime.
  69
  70 `suspend` mode::
  71
  72 This mode uses rsync to copy the container data to a temporary
  73 location (see option `--tmpdir`). Then the container is suspended and a second
  74 rsync copies changed files. After that, the container is started (resumed)
  75 again. This results in minimal downtime, but needs additional space
  76 to hold the container copy.
  77 +
  78 When the container is on a local filesystem and the target storage of the backup
  79 is an NFS server, you should set `--tmpdir` to reside on a local filesystem too,
  80 as this will result in a many fold performance improvement.
  81 Use of a local `tmpdir` is also required if you want to backup a local container
  82 using ACLs in suspend mode if the backup storage is an NFS server.
  83
  84 `snapshot` mode::
  85
  86 This mode uses the snapshotting facilities of the underlying
  87 storage. First, the container will be suspended to ensure data consistency.
  88 A temporary snapshot of the container's volumes will be made and the
  89 snapshot content will be archived in a tar file. Finally, the temporary
  90 snapshot is deleted again.
  91
  92 NOTE: `snapshot` mode requires that all backed up volumes are on a storage that
  93 supports snapshots. Using the `backup=no` mountpoint option individual volumes
  94 can be excluded from the backup (and thus this requirement).
  95
  96 NOTE: bind and device mountpoints are skipped during backup operations, like
  97 volume mountpoints with the backup option disabled.
  98
  99
 100 Backup File Names
 101 -----------------
 102
 103 Newer versions of vzdump encode the guest type and the
 104 backup time into the filename, for example
 105
 106  vzdump-lxc-105-2009_10_09-11_04_43.tar
 107
 108 That way it is possible to store several backup in the same
 109 directory. The parameter `maxfiles` can be used to specify the
 110 maximum number of backups to keep.
 111
 112 Restore
 113 -------
 114
 115 The resulting archive files can be restored with the following programs.
 116
 117
 118 `pct restore`:: Container restore utility
 119
 120 `qmrestore`:: QemuServer restore utility
 121
 122 For details see the corresponding manual pages.
 123
 124 Configuration
 125 -------------
 126
 127 Global configuration is stored in '/etc/vzdump.conf'. The file uses a
 128 simple colon separated key/value format. Each line has the following
 129 format:
 130
 131  OPTION: value
 132
 133 Blank lines in the file are ignored, and lines starting with a '#'
 134 character are treated as comments and are also ignored. Values from
 135 this file are used as default, and can be overwritten on the command
 136 line.
 137
 138 We currently support the following options:
 139
 140 include::vzdump.conf.5-opts.adoc[]
 141
 142
 143 .Example 'vzdump.conf' Configuration
 144 ----
 145 tmpdir: /mnt/fast_local_disk
 146 storage: my_backup_storage
 147 mode: snapshot
 148 bwlimit: 10000
 149 ----
 150
 151 Hook Scripts
 152 ------------
 153
 154 You can specify a hook script with option `--script`. This script is
 155 called at various phases of the backup process, with parameters
 156 accordingly set. You can find an example in the documentation
 157 directory ('vzdump-hook-script.pl').
 158
 159 File Exclusions
 160 ---------------
 161
 162 NOTE: this option is only available for container backups.
 163
 164 'vzdump' skips the following files by default (disable with the option
 165 `--stdexcludes 0`)
 166
 167  /tmp/?*
 168  /var/tmp/?*
 169  /var/run/?*pid
 170
 171 You can also manually specify (additional) exclude paths, for example:
 172
 173  # vzdump 777 --exclude-path /tmp/ --exclude-path '/var/foo*'
 174
 175 (only excludes tmp directories)
 176
 177 Configuration files are also stored inside the backup archive
 178 (in `./etc/vzdump/`) and will be correctly restored.
 179
 180 Examples
 181 --------
 182
 183 Simply dump guest 777 - no snapshot, just archive the guest private area and
 184 configuration files to the default dump directory (usually
 185 '/var/lib/vz/dump/').
 186
 187  # vzdump 777
 188
 189 Use rsync and suspend/resume to create a snapshot (minimal downtime).
 190
 191  # vzdump 777 --mode suspend
 192
 193 Backup all guest systems and send notification mails to root and admin.
 194
 195  # vzdump --all --mode suspend --mailto root --mailto admin
 196
 197 Use snapshot mode (no downtime) and non-default dump directory.
 198
 199  # vzdump 777 --dumpdir /mnt/backup --mode snapshot
 200
 201 Backup more than one guest (selectively)
 202
 203  # vzdump 101 102 103 --mailto root
 204
 205 Backup all guests excluding 101 and 102
 206
 207  # vzdump --mode suspend --exclude 101,102
 208
 209 Restore a container to a new CT 600
 210
 211  # pct restore 600 /mnt/backup/vzdump-lxc-777.tar
 212
 213 Restore a QemuServer VM to VM 601
 214
 215  # qmrestore /mnt/backup/vzdump-qemu-888.vma 601
 216
 217 Clone an existing container 101 to a new container 300 with a 4GB root
 218 file system, using pipes
 219
 220  # vzdump 101 --stdout | pct restore --rootfs 4 300 -
 221
 222
 223 ifdef::manvolnum[]
 224 include::pve-copyright.adoc[]
 225 endif::manvolnum[]
 226